“We make the sizes that sell in our stores,” Clarkson told news.com.au.

“Right now we have XS — XL and that’s because that’s what our customers want. If we were going to try a larger size we would sell them in a store that demanded larger sizes, but that hasn’t resulted in sales for us.”

Lorna Jane said while there’s not a demand for plus size active wear, and until there is she won’t deliver. Picture: Anthony WeateSource:News Corp Australia

Clarkson, who has 200 stores around the world bearing her name, reportedly worth an estimated $500 million, is a fitness force to be reckoned with.

While some critics believe the designer and business owner should be catering for all shapes and sizes, she listens to her customers — and when they ask for larger sizes, that’s when they’ll deliver.

“Any criticism that we get are people who don’t support our brand anyway. If they did they would be walking into our store and trying on the clothes, and if they didn’t fit we would say ‘OK, we need to start making those clothes in a bigger size’.

“Our brand is totally customer focused, and we haven’t felt the demand for bigger sizes. If my customer wanted bigger sizes, I would absolutely accommodate. But we have tried it and not sold it.”

Lorna Jane would stock bigger sizes if there was a demand for it.Source:News Corp Australia

With millions of followers on the Lorna Jane social media channel, IBISWorld analytics suggest one piece of the brand’s athletic apparel is sold every 19 seconds in Australia.

Her customer base, which she labels “the LJ women”, started back in 1989 when the then dental therapist and aerobics instructor made clothing patterns out of newspaper while living in Cairns.

“I had no formal training. I just made patterns out of newspaper and sewed on my Janome,” she said in an interview with The Courier Mail.

“Then women in my classes started asking me to make similar pieces, and overnight it turned into a fulltime job.”

And several months later, she came under fire for allegedly encouraging staff members to skip lunch, live on coffee and go to the gym in order to fit the “move, nourish, ­believe” philosophy.

At the time, a former store manager Amy Robinson said she was bullied by senior staff regularly about her weight and forced to work in unsafe conditions during her six months with Lorna Jane in 2012. The 39-year-old made a claim for more than $500,000 from the company for pain and suffering sustained during her ­employment.

Lorna Jane broke down during her 60 Minutes interview inSource:Supplied

In a subsequent 60 minutes interview, Clarkson said the whole year was actually a “blessing in disguise” and made her “stronger”.

“Going through that was awful ... feeling so misunderstood on a public level when it’s so far away from who you are — it was emotionally draining,” she said.

“I was really fragile and the public saw the worst of it, but what I’ve learned is that it’s good to be human and let people see that side of you. I definitely got stronger. I’m not unhappy that it happened — that’s how you grow and learn.”

A model wearing some of Lorna Jane’s activewear.Source:Supplied

Clarkson, who is currently in Sydney to promote Active Nation Day on Sunday, hopes her journey will encourage others around the world to get out and moving.

“We need a day that stops us and take note of where we are at as a nation and as individuals,” she said.

“We are time poor ... You don’t have to go out and make these huge massive changes, just small changes every day.”

Active Nation Day falls on the last Sunday of every September, and has been running for the past five years. The day is to recognise, celebrate and encourage women to mark their commitment to Active Living by taking on some exercise.